Electric-arc lamp



(No Model.) 2 Sheets-Sheet 1.

S. W. RUSHMORE.

ELECTRIC ARC LAMP.

No. 454,294. Patented June 16,1891.

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ELECTRIC ARC LAMP.

No. 454,294. Patented June 16,1891.

- UNITED STATES PATENT OFFICE.-

SAMUEL YV. RUSHMORE, OF BROOKLYN, NFAVYORK.

ELECTRIC-ARC LAMP.

SPEGIFICATXON forming part of Letters Patent No. 454,294, dated June 16,1891.

Application filed December 10, 1890. Serial No. 374,255. (No model.)

To all whom it may concern.-

Be it known that I, SAMUEL TV. RUSHMORE, a citizen of the United States,residing at Brooklyn, in the county of Kings and State of New York, haveinvented certain new and useful Improvements in Electric-Arc Lamps, ofwhich the following, with the accompanying drawings, is a specification.

My invention relates to improvements in arc lamps, and is designed toprovide a simple and effective means for controlling the movablecarbon-rod to establish the arc; and the invention consists in the novelfeatures of construction and in the several combinations hereinafter setforth and claimed.

I11 the drawings, Figure 1 is a front elevation of the lamp, the framebeing in section. Fig. 2 is a side view of the lamp. Fig. 3 is anenlarged perspective of the pivoted frame forming a part of the feedingmechanism. Fig. 4 is a vertical central section of the follower whichrests upon the movable carbonrod. Fig. 5 is a top view of the carbon-rodclamp. Fig. 6 is a central vertical section through the clamp and one ofits supportingslides.

A is a box or casing in which the working mechanism of the lamp ismounted and into which the movable carbon R extends through an opening Ain the bottom of the casing. On either side of said carbon or thecarboncarrying rod is a guide B 13', secured at the top of the case, andextending at the bottom through the opening A in the case and beingsteadied or supported byabracket F. These guides are provided withratchet-teeth b,

serves, when raised on the body of the follower, to hold said pawls awayfrom the guide- The ring can be raised upon the sleeve bars.

by allowing the follower to drop below the floor of the lamp throughopening A',where it can be reached by the hand. Projecting downward fromthe top 'of the casing are two pins a a in position to strike the top ofthe ring 0' and push it down when the carboncarrying rod is pushedentirely up.

M is a compound magnetthat is, a magnet having two coils, one of whichis in series with the arc and the other of which is in a shunt thereto.This is shown most clearlyiu the diagram Fig. 1, in which 1 is the maincoil and 2 the shunt-coil. This magnet is provided with an armature 'm,which is connected to the arm in, which in turn is pivoted to the arm (1of the section D of a doublepivoted frame. Said part D is pivoted to theposts E E and has a projecting arm d, which rests under the pivoted orspring-circuit terminal P. The lower part of the frame D is pivotallyconnected with the links I I',which are connected with the tubes or a,said tubes being adapted to slide freely in the collars 2' i, secured tothe floor of the lamp-case and carrying at their lower ends the friction-clamp N, the construction of which is most clearly shown in Fig.5. The tension of the springs of the clamp on the carbon-rod is soadjusted that said rod will not move through the clamp under theinfluence of gravity and accidental jars, but will be held by the clampand moved forward therewith, but when the carbon-rod is held from movingaway from the arc and said clamp is raised by a suitable force (such asmagnet S) the clamp will slide over the rod. Said part D is alsoprovided with projecting pins j, adapted to restin the slots in theupper end of the brackets J J. This part of the frame is provided withan arm H, having an insulated knob 7b at the end under the terminal I.The parts D D are connected by links (1 d.

S is a second magnet, having an armature s, which engages the arm ll ofthe lowersection of the (:louble-pivoted frame, so that when thearmature is raised the pinsj will ride up in the slots in which theyrest, and the clamp N will also be raised.

Referring now to Fig. 1, the circuits will be described. 3 is thepositive terminal of the lamp, and 4 the negative terminal. Thefirst-mentioned terminal is connected to the lower carbon, thencethrough the upper carbon to the coarse or series coil 1, and then to thenegative terminal of the lamp. The shunt-coil extends from the positiveterminal by wire 5 through the shunt-coil 2 to terminal 4:. Magnet S isin a circuit leading from terminal 3 to terminal P, and when saidterminal is in contact with arm (Z the circuit is completed to theupper-carbon rod and to the opposite terminal of the lamp.

The operation of the lamp will now be set forth. \Vhen the lamp is outof use, the upper carbon is down in contact with the lower carbon. Inthis position the double-pivoted or rocking frame is so tilted that knobh presses up against terminal P, raising the latter from arm d, thusholding the circuit of magnet S open. lVhen the circuit is first closedto the lamp, the series coil 1 is energized, armature m raised, andthrough said armature and the pivoted frame the clamp N is raised,thereby raising the carbon R by compressing spring 0 in the follower andestablishing the are. This at once causes current to pass through theshunt-coil i, which coil tends to counteract the series coil and tolower the armature on. As the carbons burn away, therefore, the uppercarbon is gradually carried down by the clamp under the influence of theshunt-coil. hen this feeding movement has progressed a certain distance, the arm (Z will strike the terminal P, closing the circuitthrough magnet S. This immediately raises armature s and thelowersection of the pivoted frame, and at the same time raising the clamp N,whereby it is enabled to grasp the carbon at a point farther from thearc. The carbon does not move up with the clamp, for the reason that itis locked from movement away from the are by the pawls of the follower0. As D is raised the knob h is carried. hen the frame has been raised acertain distance, it strikes the terminal P and raises said terminalaway from the arm (I. This breaks the circuit of magnet S and givesincreased power to the main magnet, Which then operates to maintainthenor-' mal are.

\Vithout limiting myself to all the details as described, what I claimis 1. The combination, in an arc lamp, of carbons and means forcontrolling the same to establish an are, said means consisting of ayielding follower upon one of said carbons, but normally held frommovement away from the are, a fixed coil or magnet, an. armature forsaid coil, and a connection between the armature and movable carbon,whereby when the coil is energized the yielding follower is compressedand the carbon is raised, substantially as described.

2. The combination, in an arc lamp, of car bons and means forcontrolling the same to establish an are, said means consisting of ayielding follower upon one of said carbons, but normally held frommovement away from the are, a fixed coil or magnet, an. armature forsaid coil, a connection between the armature and movable carbon, wherebywhen the coil is energized the yielding follower 15 compressed and thecarbon is raised, and means for unlocking the follower, so that it maybe moved away from the are, substantially as described.

The combination, in an arc lamp, of a frame, a magnet comprising a mainand a shunt coil, an armature for the magnet, one of said parts beingsupported in a fixed position by the frame, a movable carbon, a clampwhich grasps said carbon, a yielding follower, an armature for themagnet, having a connection with the clamp, whereby when the magnet isenergized the carbon is raised and the are formed and then the carbon isfed forward, substantially as described.

at. The combination, in an arc lamp, ofa frame, a magnet comprising amain and a shunt coil, an armature for the magnet, one of said partsbeing supported in a fixed position by the frame, a movable carbon, aclamp which grasps said carbon, a yielding follower, an armature for themagnet, having a connection with the clamp, whereby when the magnet isenergized the carbon is raised and the are formed and then the carbon isfed forward, a second magnet normally inoperative, but brought into anoperative circuit by movement of the clamp toward the are, an armaturefor said magnet, and a connection between the armature and clamp formoving the latter away from the are, substantially as described.

5. The combination, in an arc lamp, ot' a frame, a magnet comprising amain and a shunt coil, an. armature for the magnet, one of said partsbeing supported in a fixed position by the frame, a movable carbon, aclamp which grasps said. carbon, a yielding follower, an armature forthe magnet, having a connection with the clamp, whereby when the magnetis energized the carbon is raised and the are formed and then the carbonis fed forward, a second magnet normally inoperative, but brought intoan operative circuit by movement of the clamp toward the arc, anarmature for said magnet, a connection between the armature and clampfor moving the latter away from the arc, and a circuitbreaker in circuitwith the latter magnet,

substantially as described.

6. The combination, in an arc lamp, of carbons, one of which is movable,a clamp which grasps the movable carbon with sufficient force to hold itfrom moving through the clamp by gravity or from the effect ofaccidental jars, but which will yield to allow the clamp to slide overthe carbon when the clamp is raised, a follower on the carbon, whichmoves toward the are as the carbon consumes, but which is locked againstreverse movement, a magnet, and an armature therefor connected to theclamp for raising it, sub stantially as described.

'1'. The combination, in an arc lamp, of suit able carbons, one of whichis movable, a

. clamp for said carbon, a series coil and an armature thereforconnected with the clamp for establishing the arc, a shunt-coil actingagainst the series coil, a third coil having an armature connected tothe clamp for raising it, and means for holding the carbon from movementaway from the arc, substantially as described.

8. The combination, with a movable carbon of an arc lamp, of a clampwhich grasps the carbon sufficiently to raise it if it is free to move,but which will yield to slide over the carbon if the latter is not freeto move, a magnet or coil, an armature to move the clamp and carbon, asecond magnet and armature connected to the clamp to move it, and afollower to hold the carbon while the second magnet acts, substantiallyas described.

9. The combination of an arc-lamp carbon, feeding devices therefor, afollower consisting of a sleeve adapted to fit the carbon orcarbon-holder, a yielding head in the sleeve, one or more pawls on theoutside of the sleeve, and a guide or guides, substantially asdescribed.

10. A follower for are lamps, consisting of a sleeve adapted to fit thecarbon or carbonholder, a yielding head in the sleeve, and one or morepawls on the outside of the sleeve, in combination with a guide-bar orguide-bars provided with means for engaging the same, substantially asdescribed.

11. A follower for are lamps, consisting of a sleeve adapted to fit thecarbon or carbonholder, a yielding head in the sleeve, and one or morepawls on the outside of the sleeve,in

combination with a guide-bar or guide-bars provided with means forengaging the same, and means for holding the pawls out of engagementwhen the follower is moved away from the arc, substantially asdescribed.

12. A follower for are lamps, consisting of a sleeve adapted to fit thecarbon or carbonholder, a yielding head in the sleeve, and one or morepawls on the outside of the sleeve, in combination with a guide-bar orguide-bars provided with means for engaging the same, means for holdingthe pawls out of engagement when the follower is moved away from thearc, and means for releasing the holding device at the end of themovement of the follower, substantially as described.

13. The combination, in an arc lamp, of a reciprocating clamp for themovable carbon, two magnets, and armatures, the armatures beingoperatively connected to the clamp and each magnet attracting itsarmature in the direction to raise the clamp, said magnets being incircuit alternately, substantially as described.

14. The combination, in an arc lamp, of a reciprocating clamp for themovable carbon, a holder for the clamp, consisting of a doublepivotedframe, and two magnets and armatures therefor, said armatures beingconnected, respectively, to the two parts of the frame, substantially asdescribed.

In testimony whereof I afiix my signature, in presence of two witnesses,this 18th day of September, 1890.

SAMUEL 1V. RUSI-IMORE.

Witnesses:

II. S. SPRAGUE, F. B. S. MORGAN.

